To the Editor: Dr Lee and colleagues1 described the development and initial validation of an index to predict 4-year mortality in adults older than 50 years. I believe this index has the potential to overestimate a person's risk of mortality in some situations.

Inspection of the items of the index suggests that individuals who have excessive concerns about their health in the form of somatoform disorders such as hypochondriasis2,3 are likely to obtain inflated scores. This would be clinically important because individuals with somatoform disorders have unrealistic beliefs about the frailty of their health and because a false-positive result from their mortality index would only fuel their concerns. Persons with hypochondriasis typically believe that they have some serious undiagnosed disease, and they often misinterpret the information they receive from their physicians.2,3 Thus, they may have inflated scores on the items assessing perceived health (eg, “Has a doctor ever told you that you have . . . high blood sugar?”). People with hypochondriasis also have significant functional impairment that arises from their mistaken beliefs that their health is impaired.2,3 Thus, they may have inflated scores on the items assessing functional impairment (eg, “Because of a health problem do you have any difficulty with pulling or pushing large objects like a living room chair?”).